<div [formGroup]="form">
  <mat-form-field>
    <mat-label>Phone number</mat-label>
    <example-tel-input formControlName="tel" required></example-tel-input>
    <mat-icon matSuffix>phone</mat-icon>
    <mat-hint>Include area code</mat-hint>
  </mat-form-field>
  <p>Entered value: {{form.valueChanges | async | json}}</p>
</div>
